Soon to be owner of a new XB 600

I'm going to be getting the xb-600 bike soon and it's already in the process of being sent over the next week or so. But I would rather get some question answered ahead of time, if possible, since some of you have taken the plunge to get the xb-600 on par with other road vehicles

1.)Would it be a good idea to replace some of the screws and bolts on the bike with better quality ones after I get it or not?

2.)As far as the shunt mod goes I am more curious as to what the difference is between using a coat hanger vs. 16 gauge speaker wire like win32forth has done? As far as understanding that it allows the xb-600 to accelerate faster because the controller thinks there is a drop in current and therefore causes the voltage to go up and speed up the motor I already understand. But what I'm after is why if the bike works fine for win32forth should I use a coat hanger instead if I can do the same with 16 gauge speaker wire?

3.) Are there any personal recommendations you have for after I get the bike to do or prepare the bike for if needed (apart from the shunt mod) that you yourself would personally recommend?

4.)Is the assembly process confusing or does it just take a bit of time to understand what the directions are saying. If possible could you give pics or the process you used or the assembled parts to give me a better idea in case I or other people need to see it? ( I know it's just a few parts as far as assembly goes, but it would be helpful to get this information ahead of time to prepare for when I actually receive the bike.)

1 My own experience is the nuts and bolts are fine. Just go around the bike and make sure all are tight.

2 I just did the shunt mod yesterday and it will help with acceleration. Measured the shunt before mod and after and it was always 0 Ohms. 16ga wire will handle 22amps the coathanger? The choice is yours, however there is no air circulation in the controller so I went with the coathanger. Mine goes across the top of the two that were there due to limited space to drill the holes.

3 Get some 3M velcro and use it to hold the carpet down to the floor pan. This keeps it from blowing off in the wind and can be removed to access the battery box if needed. Then ride and have fun.

4. The front tire assembly was a bit confusing to me as to where the spacer went at first but I did get it after some thought. I will try to post a close up of the front wheel for you.

Update: XB600
1 year old this week
1659 miles (bike computer calibrated with GPS}
3 flat tires ( running slime in them now, Darn desert thorns }
Stopped by police 3 times no tickets
Longest ride 57 miles with small 2 cycle generator on floor pan charging while riding.
1 blown main fuse going up steep hill with full charge on batteries and full throttle
Replaced instrument lights with super bright LEDs and can now read them in the dark
Charge after every use / no noticable loss of battery capacity
Most rides between 5 and 10 miles / very flat here. Deming,NM.
Ran out of rear brake ajustment on the cable so had to adjust lever at the drum
Tightened the gooseneck at 1100 miles, not bad but a little loose

1.)Would it be a good idea to replace some of the screws and bolts on the bike with better quality ones after I get it or not?

I was going to, but since this is (mechanically) a bicycle, and my needs for reliability aren't that stringent (I only drive 1 mile each way to work) I have only replaced screws as they need to be replaced. Your requirements may be greater.

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2.)As far as the shunt mod goes I am more curious as to what the difference is between using a coat hanger vs. 16 gauge speaker wire like win32forth has done? As far as understanding that it allows the xb-600 to accelerate faster because the controller thinks there is a drop in current and therefore causes the voltage to go up and speed up the motor I already understand. But what I'm after is why if the bike works fine for win32forth should I use a coat hanger instead if I can do the same with 16 gauge speaker wire?

Ok, I don't want to create a conflict here, so I just want to say that the coat hanger mod is fine, and probably better (in most cases) than using a piece of heavy speaker wire. The reason I used speaker wire is as follows;

1. I didn't want to unscrew all the FETs to get to the underside of the board. Doing that, and removing the board from the chassis increases the risk that one of the FETs might not get properly re-mounted and so could fail due to overheating. In other words, I am lazy.

2. I didn't want to actually measure the shunt resistance and then attempt to calculate some theoretical reduction in shunt resistance that could solve my getting up the hill problem. It isn't that hard to actually measure the shunt, but I am not sure what percentage reduction in resistance would have done the job I wanted done, so trying to do it the right way would have turned this into a project, rather than a quick experiment.

3. The speed of the motor is limited (as I have learned) by the voltage, so the shunt mod has no effect on top end speed. All it does is allow more current to flow to the motor during the times that higher current is needed (going up hills).

4. My hills are not very steep, so I was not (overly) concerned about the motor drawing so much current that it might blow the fuse. If I tried to pull up a steep hill, It still might blow, since the speaker wire is probably acting more like a short rather than a shunt.

5. I don't have any intention of going to higher voltage (well.. that's not really true), so the current that the motor can draw isn't being increased that much (at least that is my rationalization). Actually I have been thinking about getting another battery.

6. I have been working with electronics for more years than I can count, and I looked at my requirements, and the possibility that I might blow up the extra $65 controller I bought specifically for this experiment, and went with the lazy mans solution. I figured I could always go back to the old controller.

Your milage may vary. You make the modifications, and you take the risk.

We are all here to help, but we don't take any responsibility for our, or your mistakes! As they say, let the buyer beware.

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3.) Are there any personal recommendations you have for after I get the bike to do or prepare the bike for if needed (apart from the shunt mod) that you yourself would personally recommend?

Other than the 60v mod, which I both "am" and "am not" considering, I think that some people have done some high intensity LED light mods that sound pretty interesting.

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4.)Is the assembly process confusing or does it just take a bit of time to understand what the directions are saying. If possible could you give pics or the process you used or the assembled parts to give me a better idea in case I or other people need to see it? ( I know it's just a few parts as far as assembly goes, but it would be helpful to get this information ahead of time to prepare for when I actually receive the bike.)

First, let me say that the instructions are not terrible, they are just sort of minimal.So, if you are not very mechanically inclined then you might want to get a friend to help with the assembly. But, really, it isn't that hard, and if you have repaired bicycles before, then this really isn't that much different.

Just remember to plug in the battery pack. The instructions don't say anything about that, but they ship the scooter with the battery disconnected, which makes perfect sense. So, as the last thing you do in assembly, use the key to unlock the battery pack, lift it up and plug in the battery cable under the left side rear of the battery box.

Enjoy, I am. If you don't expect too much in terms of quality, you won't be disappointed.

Were you using the generator to drive the 2.5 amp 48v charger, or some other way? The reason I ask, is that it doesn't seem like the regular SLA charger would provide sufficient charging to allow you to continue driving that far.

Also, do you happen to know what the farthest y distance you have without the charger is?

Tom,
Yes the generator was powering the stock charger. I started with a full charge and the generator running. Riding full throttle and only stoping once for a smoke. Top speed at the end of my ride was about 6mph. Needless to say it was drained.

My longest ride is 23 miles and not using full throttle, a Sunday afternoon cruise so to speak and I still had a top speed of 16mph and was showing about 1/4 charge left.

I just did the shunt mod so I am trying to only use the extra acceleration when needed. I watch the battery gauge and try not to accelerate below the full line on the gauge when taking off from a stop. I would rather take a little longer getting up to speed than push my scooter home!!

Tom,
Yes the generator was powering the stock charger. I started with a full charge and the generator running. Riding full throttle and only stoping once for a smoke. Top speed at the end of my ride was about 6mph. Needless to say it was drained.

My longest ride is 23 miles and not using full throttle, a Sunday afternoon cruise so to speak and I still had a top speed of 16mph and was showing about 1/4 charge left.

I just did the shunt mod so I am trying to only use the extra acceleration when needed. I watch the battery gauge and try not to accelerate below the full line on the gauge when taking off from a stop. I would rather take a little longer getting up to speed than push my scooter home!!

Happy scooting
JamesS

JamesS,

Thanks for the answer. It is interesting to note, that if you had a 48 volt power supply, at say 10 amps, that ran from 110 volts, you could have connected it directly to the battery, and basically been running the XB-600 from the generator directly and the batteries would not have run down at all. Most likely your gas powered generator would be able to put out the required 500 watts or so without much difficulty, and probably wouldn't have used much more gas. Then you could call it a hybrid! Hmm..., food for thought!

By the way, a 48 volt power supply wouldn't be that hard to build, and it wouldn't need to be rated at 10 amps, even 5 - 7 amps would be enough to keep the batteries charged if you weren't running at full throttle.

So what kind of generator were you using, and where can I get one that is quiet, and really small?

I got the generator at a auto parts store for $89.00. Its 64cc 2 stroke 1200w with a 12v 8amp tap as well as 2, 110 outlets. With it tied down to the battery handles on the floor pan I put my pedals on, both pointing down so I had a place for my feet. It is really not that quiet, sounds like a weed wacker. Funny how when you twist the throttle on the scooter or let off the generator keeps running the same. We are so conditioned to expect a motor to coinside with throttle postion.

I agree about building a power supply not being to hard and for charging batterys it wouldn't have to be all that clean. I am sure the batteries would filter out most of the ripple. Hmmm maybe a new project in the works

Hmm.. Maybe I will have to look at my local auto part store to see if I can find a low cost generator. It does sound like it would make an interesting project, something like "Worlds first hybrid scooter!"

Once the bike arrives I'll try assembling it and test drive it to see how well it rides. I don't have too high a set of expectations for the bike so I might only mod it if it comes down to it or I have some time to spare. Otherwise I'll let it stay normal and ride it like it was made to be ridden. As well, I'll also check what you guys recommended just in case the bike needs it and in case I need to contact xtreme for anything that was damaged during delivery.

But for now here's to hoping it arrives well and safe *fingers crossed*.

And yes, the idea for using a gas powered generator to extend the range sounds like a great idea. It might actually work well as a backup in the case of long scooter trips and a lack of battery power. For those times when you just don't know what to expect :)

Sure I don't see why not? There are already methods to refine the different types of fuels, biofuel, e-85, and others currently. Although most are in the prototype stage and although usable are not very cost effective. However, I suppose it could be used on the small scale provided you could maximize the output of the fuel derived from most of these biofuels. You could probably search for motors or generators designed to use biofuels and see how well they are doing, and probably order it if you want too. Although it would probably be a good idea to make sure it can use either a broad spectrum of biofuels, or is very efficient with one easy to ultra-refine biofuel.

The second route is of course to make your own motor that uses biofuel that you yourself can make or find to use :)

Tesla,
To get back on topic, here is the pic of the front wheel. Notice the long spacer on the axle is on the left in this pic and there is a short spacer on the brake side of the axle. A black rubber washer is on the axle against the bearing before putting the front brake shoe in place. You can't see it in a pic, I would have to take front wheel off and pull the brake apart to show you.. It may be hard from the pic to even know that you are looking at a spacer, but once you have the parts in your hand it should be clearer

Here are a few tidbits of information about the shunt mod, and the choice of what to use.

The shunt that is already installed on the controller is in the order of milli-ohms.. Probably somewhere between .003 and .01 ohms. a .002 ohm resistor will drop about 40 millivolts at 20 amps.

The items recommended so far have been 1 1/2 inch of coat hanger wire, and a paper clip bent into a loop. (none of these have had any scientific reasons given except they don't conduct electricity as well as copper, so they have some resistance.

Coat hanger characteristics: A thin coat hanger measures about .076 inches across, which is approximately 12.5 gage. 12.gage steel wire has a resistance of 10.61 ohms/1000 feet. so if your coat hanger shunt is 2 inches long, it will have a resistance of .0018 ohms. Without making exact calculations, that amounts to almost tripling the amount of current you will allow to flow through your circuit... let's say 50 amps.

A small paper clip is made of 19 gage steel wire. Cut in half, one paper clip loop is around 2 inches total length. 19 gage steel wire has a resistance of 55 ohms/12000 inches, so your shunt will have a resistance of (55*2)/12000 = .0092. Adding that to what's already there, we're still probably well above what the fuse in the circuit can handle.

Each of these mods is effectively eliminating the current limiter, and allowing the controller to put out as much current as the battery can pump through the resistance of the motor, which I'm guessing is about 15 amps or so. (15 amps * 50 volts = 750 Watts)

If you use copper wire, you will have to go down to about 22 gage and 5 inches of wire to get anywhere near the resistance of the paper clip.

Bottom line... all these mods work to defeat the current limiter, which will give your bike more torque. You probably won't break anything, because unless you run 60 volts through the motor continuously, you'll not burn out the motor before you blow your fuse.

Personally, I'm inclined to make my mod with about 4 or 5 inches of 18 gage steel wire bought from a hardware store, wind it into a little coil where the coils aren't touching each other, and surface solder it to the top of the Printed circuit board. That way, I'm at least making an attempt to keep my current limiter somewhat active.

I would not argue with you about your conclusions with respect to adding an additional shunt in parallel to the existing shunt.

However, my experience with the shunt mod (I used 2 inch piece of 16 gauge copper wire), and the conversion to 60 volts, leads me to believe that the current limiting factor must almost surely be the internal resistance of the motor itself. I have only finished the 60 volt mod yesterday, and I have only today's experience, but I have used full throttle from relatively slow speeds, accelerating up my minor hills, and I have not blown the 30 Amp fuse. This implies to me, that the shunt, which was originally limiting the current, is no longer doing that, but it doesn't matter. Applying 60 volts to the XB-600 motor simply doesn't draw 30 Amps. It does cause the motor to get warm, and it does cause the controller to get warm, but it doesn't appear to exceed the 30 Amp limit. Now that doesn't mean I am not planning to go to the auto parts store and get some spare fuses, or perhaps a circuit breaker for insurance, because I am.

Perhaps someone with an Amp meter can chime in here, and tell us how much current is really being drawn at full throttle up a hill, at various speeds, with 48 volts, 60 volts, and 72 volts. Any volunteers?